Preheat oven to 350°F (175°C) and line an 8x8 inch square baking pan with parchment paper, leaving an overhang on two sides.
In a large mixing bowl, combine the melted butter, granulated sugar, and light brown sugar, whisking until the mixture is smooth and combined.
Add the eggs, vanilla extract, and almond extract; whisk vigorously for 60 seconds until the batter lightens in color.
Gently fold in the all-purpose flour and salt using a spatula until just combined and no dry streaks remain.
Fold in the rainbow sprinkles and white chocolate chips until evenly distributed throughout the batter.
Spread the batter into the prepared baking pan, smoothing the top with a spatula to ensure an even thickness.
Bake for 25 to 30 minutes, or until the edges are lightly golden and a toothpick inserted into the center comes out with a few moist crumbs.
Remove from the oven and allow the blondies to cool completely in the pan on a wire rack before lifting out by the parchment paper and slicing into 16 squares.